Steel unfazed by auto aluminum gains

NEW YORK  The steel industry remains upbeat about the continued viability of steel use in automotive manufacturing despite a noticeable increase in the use of aluminum alloys and carbon fiber, according to Lawrence W. Kavanagh, president of the Steel Market Development Institute, Washington.

"As we methodically eliminate the lightweighting advantage of alternative materials, we increase both the cost advantage of our material and the life cycles emissions advantage of our material," Kavanagh said during a press conference at the North American International Auto Show in Detroit. "In short, we protect the environment as vigorously as we protect the driver."

Kavanagh pointed to the 2014 Cadillac ATS as evidence of steels continued favorability among major automakers. "The Cadillac ATS is a really good example for the adoption of advanced high-strength steels (AHSS): about 40 percent of that vehicle is AHSS," he said, noting that the average strength of steel in the ATS is a little over 400 megapascals. "Our Future Steel Vehicle project was almost 800 megapascals, so there is much more room to go with lightweighting with todays materials."

Cadillacs chief engineer for the ATS, Dave Masch, confirmed Kavanaghs data. "We have multiple different grades of steel throughout the car," he said in an interview with AMM. "We have some steel in front in the motor compartment rails that is designed to take high crash deformations. We have ultra-high-strength steels in the side frame area of the vehiclethe B-pillar, the rocker, up in the roof pillar areas." Masch noted that the ATS also utilizes low-grade steel for "some of the body panels, specifically to get crisper lines and for formability reasons."

But while steel will continue to be heavily featured across Cadillacs array of vehicles, aluminum also has become an attractive option in recent years, Masch told AMM. "We already have an extensive amount of aluminum on the ATS as it isalmost the entire front suspension is aluminum," he said. "Its quite possible that our use of aluminum will increase over the next few years. The best way to describe it is purposeful material application; its all about lightweighting, fuel efficiency and performance."

Fords unveiling of its redesigned F-150 pickup truck featuring a body made from aluminum alloy (amm.com, Jan. 13), was a key talking point at the auto show earlier this week, but Kavanagh said the long-awaited vehicle had already been taken into account. "The decision with the F-150 is madeit was made a long time ago," he said. "Our eyes are focused forward and we are working on developing steel-intensive solutions that keep steel as the dominant material for vehicles that will be coming out in the next few years."

Kavanagh closed the press conference by noting that aluminum manufacturers are going to struggle to properly recycle material when current aluminum-bodied vehicles reach end of life. "They cant achieve the recycling they want to without a great increase in demand, and they cant achieve the emissions drop they want to without a great increase in recycling. Its a bit of a Catch-22," he said. "With steel, you melt it, you build it, you use it, you melt it, it becomes something else and theres no issue there. The aluminum arguments are only true if they take a big gain in market share."